The ROM code supports booting from eMMC memories, with the following conditions:
- eMMC memory devices compliant with Embedded MultiMediaCard (eMMC) eMMC/Card Product Standard, High Capacity, including Reliable Write Boot, and Sleep Modes, Dual Data Rate, Multiple Partitions Supports and Security Enhancement v4.5 from the MMCA Technical Committee. The exception is the hardware reset feature. For example, if the user software requires eMMC device hardware reset, it can be accomplished with a GPIO. To correctly boot from eMMC when using Alternative Boot Operation mode, it is recommended to tie the eMMC device RST_N signal to the platform warm reset.
- eMMC device connected to the device MMC2 controller I/O interface (only one device can be connected to the bus).
- The eMMC memory device is powered externally by a PMIC or other power supply.
- When booting from user area: Initial (default) 1-bit SDR mode, optional 4-bit and 8-bit SDR- and DDR-modes using Configuration Header
- Initial SDR- and DDR- modes supported
- Clock frequency when booting from user area:
- Identification mode: 400 kHz
- Data transfer mode: 10 MHz, optionally up to 48 MHz by Configuration Header
- Support for eMMC boot partitions. eMMC booting from boot partitions (BPs), which is typical for booting in Alternative Boot operation mode, is always done at 8-bit / 48 MHz / DDR.